System and method for sequestered wash buffered reuse

ABSTRACT

A system includes a fluidic device, a flow control valve, a first reagent fluid reservoir fluidly connectable to the fluidic device by the flow control valve, a first fluid buffer reservoir fluidly connectable to the fluidic device by the flow control valve, and a common fluid buffer source fluidly connectable to the fluidic device by the flow control valve. The flow control valve permits flow comprising: (i) flow from the first reagent fluid reservoir to the fluidic device, (ii) flow from the common fluid buffer source to the fluidic device, (iii) flow from the fluidic device to the first fluid buffer reservoir, (iv) flow from the first reagent fluid reservoir to the fluidic device, and (v) flow from the first fluid buffer reservoir to the fluidic device.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit under 35 U.S.C. § 119(e) of thefiling date of provisional patent application Ser. No. 62/741,812 filedOct. 5, 2018, the disclosure of which is incorporated herein byreference.

BACKGROUND

Various assay protocols for clinical and molecular processes areimplemented in systems that include fluid handling equipment to delivervarious types of reagent fluids held in one or more reagent storagecomponents to a reagent destination to conduct one or more fluidoperations, such as mixing, processing, reaction, detection, etc.Typically, after each fluid operation, a fluid buffer solution isintroduced through the fluidic device to flush out any unused reagentmolecules remaining from the previous fluid operation, thereby ensuringthat the reagent fluid used in the next fluid operation is notcontaminated by remnant reagent molecules. To have a sufficient amountof fluid buffer to flush the fluidic device after each fluid operation,systems, in particular the fluidic cartridge, typically house largevolumes of fluid buffer. Housing large volumes of fluid buffer, however,can be cumbersome as fluid cartridges are limited in space availabilityas size reduction is pursued. Moreover, housing large volumes of fluidbuffer increases the costs of conducting the various fluid operations.

SUMMARY

The following presents a simplified summary in order to provide a basicunderstanding of some aspects described herein. This summary is not anextensive overview of the claimed subject matter. It is intended toneither identify key or critical elements of the claimed subject matternor delineate the scope thereof. Its sole purpose is to present someconcepts in a simplified form as a prelude to the more detaileddescription that is presented later.

Aspects of the disclosure encompass a method comprising: a step (a) ofmoving an aliquot of first reagent fluid into a fluidic device; (b)after step (a), moving a volume of fluid buffer into the fluidic device;(c) after step (b), moving at least a portion of the volume of fluidbuffer moved in step (b) into a first fluid buffer reservoir; (d) afterstep (c), moving an aliquot of second reagent fluid into the fluidicdevice; (e) after step (d), moving a volume of fluid buffer into thefluidic device; and (f) after step (e), moving at least a portion of thevolume of fluid buffer moved in step (e) into a second fluid bufferreservoir.

Aspects of the disclosure encompass a system comprising: a fluidicdevice, a flow control valve, a first reagent fluid reservoir fluidlyconnectable to the fluidic device by the flow control valve, a firstfluid buffer reservoir fluidly connectable to the fluidic device by theflow control valve, and a common fluid buffer source fluidly connectableto the fluidic device by the flow control valve. In some examples, theflow control valve permits flow comprising: (i) flow from the firstreagent fluid reservoir to the fluidic device, (ii) flow from the commonfluid buffer source to the fluidic device, (iii) flow from the fluidicdevice to the first fluid buffer reservoir, (iv) flow from the firstreagent fluid reservoir to the fluidic device, and (v) flow from thefirst fluid buffer reservoir to the fluidic device.

Aspects of the disclosure encompass a computer readable medium encodedwith computer-executable instructions that, when executed by a computercontroller of an automated system, causes the system to execute thefollowing system processes: (a) move an aliquot of first reagent fluidinto a fluidic device; (b) after process (a), move a volume of fluidbuffer into the fluidic device; (c) after process (b), move at least aportion of the volume of fluid buffer moved in process (b) into a firstfluid buffer reservoir; (d) after process (c), move an aliquot of secondreagent fluid into the fluidic device; (e) after process (d), move avolume of fluid buffer into the fluidic device; and (f) after process(e), move at least a portion of the volume of fluid buffer moved inprocess (e) into a second fluid buffer reservoir.

Other features and characteristics of the subject matter of thisdisclosure, as reservoir as the methods of operation, functions ofrelated elements of structure and the combination of parts, andeconomies of manufacture, will become more apparent upon considerationof the following description and the appended claims with reference tothe accompanying drawings, all of which form a part of thisspecification, wherein like reference numerals designate correspondingparts in the various figures.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated herein and form partof the specification, illustrate various examples of the subject matterof this disclosure. In the drawings, like reference numbers indicateidentical or functionally similar elements.

FIG. 1 is a schematic view of an exemplary system for sequestering andreusing two or more reagent fluids and fluid buffers through a fluidicdevice.

FIG. 2 is a schematic view of the system performing a first reagentoperation.

FIG. 3 is a schematic view of the system performing a first reagentreverse.

FIG. 4 is a schematic view of the system performing a first step of afirst wash operation.

FIG. 5 is a schematic view of system performing a second step of thefirst wash operation.

FIG. 6 is a schematic view of the system performing a first bufferreverse.

FIG. 7 is a schematic view of the system performing a second reagentoperation.

FIG. 8 is a schematic view of the system performing a second reagentreverse.

FIG. 9 is a schematic view of the system performing a first step of asecond wash operation.

FIG. 10 is a schematic view of the system performing a second step ofthe second wash operation.

FIG. 11 is a schematic view of the system performing a second bufferreverse.

FIG. 12 is a schematic view of the system performing a third reagentoperation.

FIG. 13 is a schematic view of the system performing a third reagentreverse.

FIG. 14 is a schematic view of the system performing a first step of athird wash operation.

FIG. 15 is a schematic view of the system performing a second step ofthe third wash operation.

FIG. 16 is a schematic view of the system performing a third bufferreverse.

FIG. 17 is a schematic view of the system performing a fourth reagentoperation.

FIG. 18 is a schematic view of the system performing a fourth reagentreverse.

FIG. 19 is a schematic view of the system performing a fourth washoperation.

FIG. 20 is a flow chart of an exemplary method for sequestering andreusing two or more reagent fluids and fluid buffers through a fluidicdevice.

FIG. 21 is a schematic diagram of the system comprising a fluidcartridge incorporated into a processing instrument.

DETAILED DESCRIPTION

While aspects of the subject matter of the present disclosure may beembodied in a variety of forms, the following description andaccompanying drawings are merely intended to disclose some of theseforms as specific examples of the subject matter. Accordingly, thesubject matter of this disclosure is not intended to be limited to theforms or examples so described and illustrated.

Unless defined otherwise, all terms of art, notations and othertechnical terms or terminology used herein have the same meaning as iscommonly understood by one of ordinary skill in the art to which thisdisclosure belongs. All patents, applications, published applicationsand other publications referred to herein are incorporated by referencein their entirety. If a definition set forth in this section is contraryto or otherwise inconsistent with a definition set forth in the patents,applications, published applications, and other publications that areherein incorporated by reference, the definition set forth in thissection prevails over the definition that is incorporated herein byreference.

Unless otherwise indicated or the context suggests otherwise, as usedherein, “a” or “an” means “at least one” or “one or more.”

This description may use relative spatial and/or orientation terms indescribing the position and/or orientation of a component, apparatus,location, feature, or a portion thereof. Unless specifically stated, orotherwise dictated by the context of the description, such terms,including, without limitation, top, bottom, above, below, under, on topof, upper, lower, left of, right of, in front of, behind, next to,adjacent, between, horizontal, vertical, diagonal, longitudinal,transverse, radial, axial, etc., are used for convenience in referringto such component, apparatus, location, feature, or a portion thereof inthe drawings and are not intended to be limiting.

Furthermore, unless otherwise stated, any specific dimensions mentionedin this description are merely representative of an exampleimplementation of a device embodying aspects of the disclosure and arenot intended to be limiting.

The use of the term “about” applies to all numeric values specifiedherein, whether or not explicitly indicated. This term generally refersto a range of numbers that one of ordinary skill in the art wouldconsider as a reasonable amount of deviation to the recited numericvalues (i.e., having the equivalent function or result) in the contextof the present disclosure. For example, and not intended to be limiting,this term can be construed as including a deviation of ±10 percent ofthe given numeric value provided such a deviation does not alter the endfunction or result of the value. Therefore, under some circumstances aswould be appreciated by one of ordinary skill in the art a value ofabout 1% can be construed to be a range from 0.9% to 1.1%.

As used herein, the term “adjacent” refers to being near or adjoining.Adjacent objects can be spaced apart from one another or can be inactual or direct contact with one another. In some instances, adjacentobjects can be coupled to one another or can be formed integrally withone another.

As used herein, the terms “substantially” and “substantial” refer to aconsiderable degree or extent. When used in conjunction with, forexample, an event, circumstance, characteristic, or property, the termscan refer to instances in which the event, circumstance, characteristic,or property occurs precisely as reservoir as instances in which theevent, circumstance, characteristic, or property occurs to a closeapproximation, such as accounting for typical tolerance levels orvariability of the examples described herein.

As used herein, the terms “optional” and “optionally” mean that thesubsequently described, component, structure, element, event,circumstance, characteristic, property, etc. may or may not be includedor occur and that the description includes instances where thecomponent, structure, element, event, circumstance, characteristic,property, etc. is included or occurs and instances in which it is not ordoes not.

A “reagent” as used herein refers to any substance or combinationthereof that participates in a molecular assay, other than samplematerial and products of the assay. Exemplary reagents includenucleotides, enzymes, amplification oligomers, probes, and salts.

The term “buffer” as used herein refers to any solution with acontrolled pH that may serve to dissolve a solid (e.g., lyophilized)substance (e.g., reagent, sample, or combination thereof) or as adiluent to dilute a liquid (e.g., a liquid reagent, liquid sample, orcombination thereof; or a solution of a reagent, sample, or combinationthereof).

According to various examples, assemblies and devices as describedherein may be used in combination with a fluid cartridge that maycomprise one or more fluid processing passageways including one or moreelements, for example, one or more of a channel, a branch channel, avalve, a flow splitter, a vent, a port, an access area, a via, a bead, areagent containing bead, a cover layer, a reaction component, anycombination thereof, and the like. Any element may be in fluidcommunication with another element.

All possible combinations of elements and components described in thespecification or recited in the claims are contemplated and consideredto be part of this disclosure. It should be appreciated that allcombinations of the foregoing concepts and additional concepts discussedin greater detail below (provided such concepts are not mutuallyinconsistent) are contemplated as being part of the inventive subjectmatter disclosed herein. In particular, all combinations of claimedsubject matter appearing at the end of this disclosure are contemplatedas being part of the inventive subject matter disclosed herein.

In the appended claims, the term “including” is used as theplain-English equivalent of the respective term “comprising.” The terms“comprising” and “including” are intended herein to be open-ended,including not only the recited elements, but further encompassing anyadditional elements. Moreover, in the following claims, the terms“first,” “second,” and “third,” etc. are used merely as labels, and arenot intended to impose numerical requirements on their objects.

The term “fluid communication” means either direct fluid communication,for example, two regions can be in fluid communication with each othervia an unobstructed fluid processing passageway connecting the tworegions or can be capable of being in fluid communication, for example,two regions can be capable of fluid communication with each other whenthey are connected via a fluid processing passageway that can comprise avalve disposed therein, wherein fluid communication can be establishedbetween the two regions upon actuating the valve, for example, bydissolving a dissolvable valve, bursting a burstable valve, or otherwiseopening a valve disposed in the fluid processing passageway.

Fluidic System

While reusing fluid buffer after being flushed through the fluidicdevice curtails the amount of fluid buffer needed for a fluid sequenceprocess, used fluid buffer typically includes remnants of the activereagent since sequencing procedures can instruct fluid handlingequipment to introduce fluid buffers into the fluidic device directlyafter introducing the active reagent through the fluidic device.Consequently, mixing reused fluid buffer with other fluid operations ofthe sequence process can further contaminate the fluid buffer supply tothe fluidic device and/or compromise the integrity of the fluidoperations by inadvertently introducing remnant reagents from a priorfluid operation from the reused fluid buffer.

Thus, there is a need for improved fluidic systems and methods thatallow fluid buffer to be both sequestered and reused in a sequencingprocess to avoid contamination and reduce the volume of fluid bufferneeded to be stored by the fluidic cartridge to conduct a fluid sequenceprocess.

According to various examples, a system is configured to sequester andreuse reagent fluids and fluid buffers directed through a fluidic deviceby comprising one common fluid buffer reservoir to hold fresh, unusedfluid buffer and at least one dedicated fluid buffer reservoir dedicatedto holding fluid buffer that has been used to flush each differentreagent through the fluidic device. The system may further comprise aflow control valve operatively associated with the common fluid bufferand the at least one dedicated fluid buffer reservoir to selectivelyfluidly connect any one of the common fluid buffer reservoir and the atleast one dedicated fluid buffer reservoir to the fluidic device duringa wash operation. Accordingly, by sequestering and reusing fluid bufferthrough the use of one or more dedicated fluid buffer reservoirs, thesystem minimizes the volume of fluid buffer used in a fluid process,such as a fluid sequencing operation, for example asequencing-by-synthesis (SBS) operation that includes a cleave process,a scavenger process, an incorporation process, and a scan processinterposed by one or more wash operations.

FIGS. 1-19 show an example system 100 for sequestering and reusingreagent fluid and fluid buffer during two or more fluid operations. Insome examples, the system 100 comprises a fluidic device 102, an inletchannel 103, a flow control valve 104, an outlet channel 105, a pump106, a set of fluid reservoirs 110, and a set of connecting channels130. In some examples, the system 100 is part of a fluid cartridge (notshown) supporting various components of the system 100, such as, thefluidic device 102, the flow control valve 104, the pump 106, and theset of fluid reservoirs 110, although one or more components of thesystem 100 may not be supported on a common fluid cartridge or othersupporting structure.

As shown in FIG. 1, the fluidic device 102 (e.g., flow cell) is fluidlyconnected to the flow control valve 104 by the inlet channel 103. In oneexample, the fluidic device 102 is a flow cell comprising a first glasslayer (not shown) and a second glass layer (not shown) secured togetherand defining one or more channels (not shown) therein that can befluidically manipulated and optically detected. In various examples, thefluidic device 102 may include a fluid inlet 107, a fluid outlet 108,and one or more fluid channels (not shown) are fluidly connected to thefluid inlet and the fluid outlet to allow fluid processing, such as achemical or biochemical assay or other process or reaction, to takeplace. In various examples, the fluidic device 102 is configured toallow the introduction of various types of fluids (e.g., reagents,buffers, reaction media) into the fluid inlet 107 to undergo fluidprocessing within the one or more fluid channels. In various examples,fluidic device 102 is further configured to allow the various types offluids to be flushed out of the one or more fluid channels through thefluid outlet 108.

In the example shown in FIGS. 1-19, the inlet channel 103 fluidlyconnects the fluid inlet 107 of the fluidic device 102 to the flowcontrol valve 104, and the outlet channel 105 fluidly connects the fluidoutlet 108 of the fluidic device 102 to the pump 106. In other examples(not shown), the system 100 may include two or more channels to fluidlyconnect the fluidic device 102 to the flow control valve 104 and two ormore channels to fluidly connect the fluidic device 102 to the pump 106.

In some examples, the set of fluid reservoirs 110 comprises two or morereagent fluid reservoirs 112, 114, 116, and/or 118. In the example shownin FIG. 1, the two or more reagent fluid reservoirs includes a firstreagent fluid reservoir 112, a second reagent fluid reservoir 114, athird reagent fluid reservoir 116, and a fourth reagent fluid reservoir118, although any number of reagent fluid reservoirs is contemplated bythis disclosure. The different reagent fluid reservoirs 112, 114, 116,and/or 118 of the set of fluid reservoirs 110 may have the same orvarying sizes (i.e., volumes)—e.g., all reagent fluid reservoirs 112,114, 116, and 118 may have the same volume, all reagent fluid reservoirs112, 114, 116, and 118 may have different volumes, or a subset of thereagent fluid reservoirs 112, 114, 116, and/or 118 may have the samevolume and a subset of the reagent reservoirs 112, 114, 116, and/or 118may have different volumes—depending on the necessary storage volume ofthe reagent to be stored in each reagent fluid reservoir.

In some examples, the first reagent fluid reservoir 112 holds a firstreagent fluid 122 comprising a solvent and a first reagent directed to afirst reagent operation (e.g., cleave). In some examples, the secondreagent fluid reservoir 114 holds a second reagent fluid 124 comprisinga solvent and a second reagent directed to a second reagent operation(e.g., scan). In some examples, the third reagent fluid reservoir 116holds a third reagent fluid 126 comprising a solvent and a third reagentdirected to a third reagent operation (e.g., incorporation). In someexamples, the fourth reagent fluid reservoir 128 holds a fourth reagentfluid 128 comprising a solvent and a fourth reagent directed to a fourthreagent operation (e.g., scavenger).

In some examples, the set of fluid reservoirs 110 comprises two or morefluid buffer reservoirs 111, 113, 115, and/or 117. In the example shownin FIG. 1, the two or more fluid buffer reservoirs includes a commonfluid buffer source or reservoir 111 and at least one dedicated fluidbuffer reservoir 113, 115, and/or 117, each associated with one of thereagent fluids 122, 124, 126, and/or 128. In the examples shown in FIGS.1-19, the at least one dedicated fluid buffer reservoir comprises afirst fluid buffer reservoir 113, a second fluid buffer reservoir 115,and/or a third fluid buffer reservoir 117, although any number ofdedicated fluid buffer reservoirs is contemplated by this disclosure.The different fluid buffer reservoirs 111, 113, 115, and/or 117 of theset of reservoirs 110 may have the same or varying sizes (i.e.,volumes)—e.g., all fluid buffer reservoirs 111, 113, 115, and/or 117 mayhave the same volume, all fluid buffer reservoirs 111, 113, 115, and/or117 may have different volumes, or a subset of the fluid bufferreservoirs 111, 113, 115, and/or 117 may have the same volume and asubset of the fluid buffer reservoirs 111, 113, 115, and/or 117 may havedifferent volumes—depending on the necessary storage volume of thereagent to be stored in each reagent fluid reservoir.

In some examples, each of the dedicated fluid buffer reservoirs 113,115, and/or 117 holds a volume of fluid that is at least 30% of a volumeof fluid held by the fluidic device 102. In some examples, each of thededicated fluid buffer reservoirs 113, 115, and/or 117 is a cachechannel comprising a consistent cross-sectional dimension across alength thereof. In some examples, each of the dedicated fluid bufferreservoirs 113, 115, and/or 117 is a cache well comprising across-sectional dimension larger than a cross-sectional dimension of itsassociated connecting channel 130. In some examples, the cache-well doesnot include any sharp edges or various topographical features and isconfigured to minimize bubble nucleation such that the cache-well doesnot accumulate bubbles as fluid is pushed in and out of the reservoir.

In the examples shown in FIGS. 1-19, the common fluid buffer reservoir111 holds a common fluid buffer 121 (e.g., wash solution that includessalt-water and soap) that has not been flushed through the fluidicdevice 102. In various examples, each of the dedicated buffer reservoirs113, 115, and/or 117 holds a sequestered fluid buffer that has beenflushed through the fluidic device 102 following a reagent operationconducted in the fluidic device 102, e.g., with one of the reagentfluids 122, 124, and/or 126, although initially before any reagentoperations have occurred, the dedicated fluid buffer reservoirs 113,115, and/or 117 may hold unused fluid buffer.

In the examples shown in FIG. 6, the first buffer reservoir 113 holds afirst fluid buffer 123 that includes a mixture of used fluid buffer 602that has been flushed through the fluidic device 102 after the firstreagent fluid 122 has been directed through the fluidic device 102during the first reagent operation. In the examples shown in FIG. 11,the second buffer reservoir 115 holds a second fluid buffer 125 thatincludes a mixture of used fluid buffer 1102 that has been flushedthrough the fluidic device 102 after the second reagent fluid 124 hasbeen directed through the fluidic device 102 during the second reagentoperation. In the examples shown in FIG. 16, the third buffer reservoir117 holds a third fluid buffer 127 that includes a mixture of used fluidbuffer 1602 that has been flushed through the fluidic device 102 afterthe third reagent fluid 126 has been directed through the fluidic device102 during the fourth reagent operation.

In some examples, the system may not include a dedicated fluid bufferreservoir for every reagent. For example, system and processes shown inFIGS. 1-20 do not include a dedicated fluid buffer reservoir associatedwith the fourth reagent fluid 128, other example systems and processesmay include a dedicated fluid buffer reservoir associated with the everyreagent fluid.

In the example shown in FIGS. 1-19, the set of connecting channels 130comprises a respective connecting channel 131 extending from itsassociated fluid reservoir 111, 112, 113, 114, 115, 116, 117, or 118 tothe flow control valve 104, such that the flow control valve 104 isfluidly connected to each fluid reservoir 111, 112, 113, 114, 115, 116,117, or 118 of the set of fluid reservoirs 110. In other examples (notshown), the set of connecting channels 130 may include two or morechannels to fluidly connect a respective fluid reservoir 111, 112, 113,114, 115, 116, 117, or 118 to the flow control valve 104, such as afront connecting channel (such as the respective connecting channel 131shown) and a rear connecting channel (not shown) such that the usedfluid buffer can be recycled to the rear of the respective fluidreservoir 111, 112, 113, 114, 115, 116, 117, or 118, opposite the frontconnecting channel.

Flow control valve 104 is constructed and arranged to selectively,fluidly connect one of the fluid reservoirs 111, 112, 113, 114, 115,116, 117, or 118 of the set of fluid reservoirs 110 to the inlet channel103, and thus, to the fluidic device 102. According to various examples,the flow control valve 104 comprises a rotary valve for selectivelyconnecting to one of the connecting channels 131 for a respective fluidreservoir 111, 112, 113, 114, 115, 116, 117, or 118.

In the example shown in FIGS. 1-19, the flow control valve 104 is arotary valve comprising a rotary body 150 and valve selector channel152. In some examples, the rotary body 150 is configured to rotatebetween a plurality of angular positions so that the valve selectorchannel 152 may fluidly connect any one of the fluid reservoirs 111,112, 113, 114, 115, 116, 117, or 118 to a valve outlet port via arespective inlet port for each fluid reservoir. When the rotary body 150is rotated to an angular position such that the valve selector channel152 is aligned with the one of the inlet ports for a selected fluidreservoir 111, 112, 113, 114, 115, 116, 117, or 118, fluid may flow fromthe selected reservoir 111, 112, 113, 114, 115, 116, 117, or 118,through the valve selector channel 152, and into the valve outlet port.

In other examples (not shown), the flow control valve 104 may includeany other type of valve to selectively, fluidly connect one of the fluidreservoirs 111, 112, 113, 114, 115, 116, 117, or 118 to the inletchannel 103. In other examples (not shown), the flow control valve 104may include a valve array, such as a plurality of pinch valves orsolenoid valves and a manifold, to selectively, fluidly connect one ofthe fluid reservoirs 111, 112, 113, 114, 115, 116, 117, or 118 to theinlet channel 103.

In various examples, the pump 106, fluidly connected to the outletchannel 105, is configured to apply a pressure differential between anyone 111, 112, 113, 114, 115, 116, 117, or 118 of the first set of fluidreservoirs 110 and the outlet channel 105 to propel fluid flowbi-directionally along a respective connecting channel 131 of the set ofconnecting channels 130, the flow control valve 104, inlet channel 103,the fluidic device 102, and the outlet channel 105. Pump 106 maycomprise a syringe pump with an actuator (not shown) operativelyassociated with the syringe. In various examples, the actuator isconfigured to move a plunger of the syringe in a first direction togenerate a negative pressure differential to draw fluid through thefluidic device 102 toward (and possibly into) a barrel of the syringe.The actuator is further configured to move the plunger in a seconddirection, opposite to the first direction, to generate a positivepressure differential and expel fluid away from (and possible out of)the syringe toward a selected reservoir 111, 112, 113, 114, 115, 116,117, or 118 of the set of fluid reservoirs 110. Accordingly, by movingin a second direction to generate a positive pressure differential, thepump 106 is configured to expel fluid held in the fluidic device 102 orthe outlet channel 105 though the inlet channel 103, the flow controlvalve 104, a selected connecting channel 131, and into one of theselected fluid reservoirs 111, 112, 113, 114, 115, 116, 117, or 118.

In other examples (not shown), the pump 106 may comprise any otherpressure differential creating mechanism that is capable of reversingflow direction.

Fluid Sequence Operation of the System

In various examples, as shown in FIGS. 2-19, the system 100 sequestersand reuses reagent fluids and fluid buffers by: (i) selectivelydirecting reagent fluids from any one of the reagent fluid reservoirs112, 114, 116, and/or 118 to the fluidic device 102 to perform a reagentoperation; (ii), optionally, redirecting at least a portion of a usedreagent fluid 302, 802, 1302, and/or 1802 directed through the fluidicdevice 102 to the selected reagent fluid reservoir 112, 114, 116, and118 to be reused for a subsequent reagent operation; (iii) selectivelydirecting fluid buffers from any of the fluid buffer reservoirs 111,113, 115, and/or 117 to the fluidic device 102 to conduct a washoperation; and (iv) redirecting at least a portion of a used fluidbuffer 602, 1102, and/or 1602 directed through the fluidic device 102back to one of the dedicated fluid buffer reservoirs 113, 115, and/or117 to be reused for a subsequent wash operation.

Referring to FIG. 2, the system 100 may be set to perform a firstreagent operation, such that flow control valve 104 permits fluid flowfrom the selected first reagent fluid reservoir 112 of the set ofreservoirs 110 to the fluidic device 102. During the first reagentoperation, the flow control valve 104 is set to connect the firstreagent fluid reservoir 112 to the fluidic device 102 (e.g., byconnecting valve selector channel 152 with a corresponding connectingchannel 131 associated with the first reagent fluid reservoir 112). Thepump 106 is operated to draw the first reagent fluid 122 from the firstreagent fluid reservoir 112 through the flow control valve 104 and intothe fluidic device 102. As shown in FIG. 2, an aliquot 202 of the firstreagent fluid 122 is moved through the corresponding connecting channel131, the flow control valve 104, the inlet channel 103, the fluidicdevice 102, the outlet channel 105, and/or into a chamber of the pump106.

Referring to FIG. 3, the system 100 may be set to perform a firstreagent reverse operation, such that the pump 106 redirects at least aportion of the aliquot 202 of the first reagent fluid 122 moved in thefirst reagent operation back to the first reagent fluid reservoir 112.During the first reagent reverse operation, the flow control valve 104remains set to connect the fluidic device 102 to the first reagent fluidreservoir 112, and the pump 106 is operated to expel fluid in a reversedirection through the fluidic device 102 back into the first reagentfluid reservoir 112. As shown in FIG. 3, at least a portion 302 of thealiquot 202 of the first reagent fluid 122 moved in the first reagentoperation is received back in the first reagent fluid reservoir 112 tobe reused for one or more subsequent first reagent operations.

Referring to FIGS. 4 and 5, the system 100 may be set to perform a firstwash operation such that flow control valve 104 initially permits fluidflow from the selected first fluid buffer reservoir 113 of the set ofreservoirs 110 to the fluidic device 102, and then, optionally, permitsfluid flow from the common fluid buffer reservoir 111 of the set ofreservoirs 110 to the fluidic device 102.

As shown in FIG. 4, during a first part of the first wash operation, theflow control valve 104 is set to connect the first fluid bufferreservoir 113 to the fluidic device 102 (e.g., by connecting valveselector channel 152 with the corresponding connecting channel 131associated with the first fluid buffer reservoir 113). Pump 106 isoperated to draw an aliquot of the first fluid buffer 123 from the firstfluid buffer reservoir 113 through the fluidic device 102. As shown inFIG. 4, a first volume 402 of the first fluid buffer 123 is movedthrough the corresponding connecting channel 131, the flow control valve104, the inlet channel 103, the fluidic device 102, the outlet channel105, and/or into a chamber of the pump 106 to flush the first reagentfluid 122 remaining in the fluidic device 102. In some implementations,the first volume 402 may include a volume 602 of reused first fluidbuffer, shown in FIG. 6, in instances where the first fluid buffer 123has previously been pumped into the corresponding connecting channel131, the flow control valve 104, the inlet channel 103, the fluidicdevice 102, the outlet channel 105, and/or a chamber of the pump 106.

As shown in FIG. 5, in some examples, during a second part of the firstwash operation, after the first volume 402 of the first fluid buffer 123is flushed through the fluidic device 102, the flow control valve 104 isset to connect the common fluid buffer reservoir 111 to the fluidicdevice 102 (e.g., by connecting valve selector channel 152 with thecorresponding connecting channel 131 associated with the common fluidbuffer reservoir 111). Pump 106 is operated to draw an aliquot of thecommon fluid buffer 121 from the common fluid buffer reservoir 111through the fluidic device 102. As shown in FIG. 5, a second volume 502of the common fluid buffer 121 can be moved through the correspondingconnecting channel 131, the flow control valve 104, the inlet channel103, the fluidic device 102, the outlet channel 105, and/or into achamber of the pump 106. In some implementations, the second volume 502can mix with the first volume 402 in one or more of the correspondingconnecting channel 131, the flow control valve 104, the inlet channel103, the fluidic device 102, the outlet channel 105, and/or a chamber ofthe pump 106. Thus, if the first volume 402 includes a volume 602 ofreused first fluid buffer, shown and described in FIG. 6, the inclusionof the common fluid buffer 121 can dilute or otherwise lessen thepresence of remnant first reagent fluid 122 in the reused first fluidbuffer. In addition, by providing the common fluid buffer 121 after thereused first fluid buffer, the common fluid buffer 121 can fluidicallyseparate the reused first fluid buffer further downstream from thefluidic device 102.

In other examples, the second part of the first wash operationillustrated in FIG. 5 may be omitted and only the first fluid buffer 123for the first wash operation can be drawn from the first fluid bufferreservoir 113.

Referring to FIG. 6, the system 100 may be set to perform a first bufferreverse operation such that flow control valve 104 permits fluid flow tothe first fluid buffer reservoir 113. The pump 106 redirects a thirdvolume 602 of used fluid buffer comprising the first fluid buffer 123and/or the common fluid buffer 121 back to the first fluid bufferreservoir 113. The third volume 602 can include at least a portion ofremnant first reagent fluid 122 in addition to the first fluid buffer123 and/or the common fluid buffer 121. In some instances, thepercentage of the common fluid buffer 121 in the third volume 602 isgreater than a percentage of first fluid buffer 123 and/or reused firstfluid buffer. During the first buffer reverse operation, the flowcontrol valve 104 is set to connect the fluidic device 102 to the firstfluid buffer reservoir 113 (e.g., by connecting valve selector channel152 with the connecting channel 131 associated with the first fluidbuffer reservoir 113), and the pump 106 is operated to move fluid in areverse direction through the fluidic device 102 to the first fluidbuffer reservoir 113. As shown in FIG. 6, the third volume 602 of usedfluid buffer is received back in the first fluid buffer reservoir 113 tobe reused for one or more subsequent first wash operations. In someexamples, the third volume 602 of used fluid buffer is less than orequal to the second volume 502 moved from the common fluid bufferreservoir 111, in other examples, the third volume 602 of used fluidbuffer is greater than the second volume 502 moved from the common fluidbuffer reservoir 111, and, in other examples, the third volume 602 ofused fluid buffer is equal to the total amount of fluid buffer flushedthrough the fluidic device 102, i.e., the combined first fluid volume402 moved from the first fluid buffer reservoir 113 and second volume502 moved from the common fluid buffer reservoir 111.

Referring to FIG. 7, the system 100 may be set to perform a secondreagent operation, such that flow control valve 104 permits fluid flowfrom the selected second reagent fluid reservoir 114 of the set ofreservoirs 110 to the fluidic device 102. During the second reagentoperation, the flow control valve 104 is set to connect the secondreagent fluid reservoir 114 to the fluidic device 102 (e.g., byconnecting valve selector channel 152 with the corresponding connectingchannel 131 associated with the second reagent fluid reservoir 114). Thepump 106 is operated to draw the second reagent fluid 124 from thesecond reagent fluid reservoir 114 through the flow control valve 104and into the fluidic device 102. As shown in FIG. 7, an aliquot 702 ofthe second reagent fluid 124 is moved through the correspondingconnecting channel 131, the flow control valve 104, the inlet channel103, the fluidic device 102, the outlet channel 105, and/or into achamber of the pump 106.

Referring to FIG. 8, the system 100 may be set to perform a secondreagent reverse operation, such that the pump 106 redirects at least aportion of the aliquot 702 of the second reagent fluid 124 moved in thesecond reagent operation back to the second reagent fluid reservoir 114.During the second reagent reverse operation, the flow control valve 104remains set to connect the fluidic device 102 to the second reagentfluid reservoir 114, and the pump 106 is operated to expel fluid in areverse direction through the fluidic device 102 back into the secondreagent fluid reservoir 114. As shown in FIG. 8, at least a portion 802of the aliquot 702 of the second reagent fluid 124 moved in the secondreagent operation is received back in the second reagent fluid reservoir114 to be reused in one or more subsequent second reagent operations.

Referring to FIGS. 9 and 10, the system 100 may be set to perform asecond wash operation such that flow control valve 104 initially permitsfluid flow from the selected second fluid buffer reservoir 115 of theset of reservoirs 110 to the fluidic device 102, and then, optionally,permits fluid flow from the common fluid buffer reservoir 111 of the setof reservoirs 110 to the fluidic device 102.

As shown in FIG. 9, during a first part of the second wash operation,the flow control valve 104 is set to connect the second fluid bufferreservoir 115 to the fluidic device 102 (e.g., by connecting valveselector channel 152 with the corresponding connecting channel 131associated with the second buffer reservoir 115). Pump 106 is operatedto draw an aliquot of the second fluid buffer 124 from the second fluidbuffer reservoir 115 through the fluidic device 102. As shown in FIG. 9,a fourth volume 902 of the second fluid buffer 124 is moved through thecorresponding connecting channel 131, the flow control valve 104, theinlet channel 103, the fluidic device 102, the outlet channel 105,and/or into a chamber of the pump 106 to flush the second reagent fluid124 remaining in the fluidic device 102. In some implementations, thefourth volume 902 may include a volume 1102 of reused second fluidbuffer, shown in FIG. 11, in instances where the second fluid buffer 125has previously been pumped into the corresponding connecting channel131, the flow control valve 104, the inlet channel 103, the fluidicdevice 102, the outlet channel 105, and/or a chamber of the pump 106.

As shown in FIG. 10, in some examples, during a second part of thesecond wash operation, after the fourth volume 902 of the second fluidbuffer 124 is flushed through the fluidic device 102, the flow controlvalve 104 is set to connect the common fluid buffer reservoir 111 to thefluidic device 102 (e.g., by connecting valve selector channel 152 withthe corresponding connecting channel 131 associated with the commonfluid buffer reservoir 111). Pump 106 is operated to draw an aliquot ofthe common fluid buffer 121 from the common fluid buffer reservoir 111through the fluidic device 102. As shown in FIG. 10, a fifth volume 1002of the common fluid buffer 121 can be moved through the correspondingconnecting channel 131, the flow control valve 104, the inlet channel103, the fluidic device 102, the outlet channel 105, and/or into achamber of the pump 106. In some implementations, the fifth volume 1002can mix with the fourth volume 902 in one or more of the correspondingconnecting channel 131, the flow control valve 104, the inlet channel103, the fluidic device 102, the outlet channel 105, and/or a chamber ofthe pump 106. Thus, if the fourth volume 902 includes a volume 1102 ofreused second fluid buffer, shown and described in FIG. 11, theinclusion of the common fluid buffer 121 can dilute or otherwise lessenthe presence of remnant second reagent fluid 124 in the reused secondfluid buffer. In addition, by providing the common fluid buffer 121after the reused second fluid buffer, the common fluid buffer 121 canfluidically separate the reused second fluid buffer further downstreamfrom the fluidic device 102.

In other examples, the second part of the second wash operationillustrated in FIG. 10 may be omitted and only the second fluid buffer125 for second wash operation can be drawn from the second fluid bufferreservoir 115.

Referring to FIG. 11, the system 100 may be set to perform a secondbuffer reverse operation such that flow control valve 104 permits fluidflow to the second fluid buffer reservoir 115. The pump 106 redirects asixth volume 1102 of used fluid buffer comprising the second fluidbuffer 125 and/or the common fluid buffer 121 back to the second fluidbuffer reservoir 115. The sixth volume 1102 can include at least aportion of remnant second reagent fluid 124 in addition to the secondfluid buffer 125 and/or the common fluid buffer 121. In some instances,the percentage of the common fluid buffer 121 in the sixth volume 1102is greater than a percentage of second fluid buffer 125 and/or reusedsecond fluid buffer. During the second buffer reverse operation, theflow control valve 104 is set to connect the fluidic device 102 to thesecond fluid buffer reservoir 115 (e.g., by connecting valve selectorchannel 152 with the connecting channel 131 associated with the secondfluid buffer reservoir 115), and the pump 106 is operated to move fluidin a reverse direction through the fluidic device 102 to the secondfluid buffer reservoir 115. As shown in FIG. 11, the sixth volume 1102of used fluid buffer is received back in the second fluid bufferreservoir 115 to be reused for one or more subsequent second washoperations. In some examples, the sixth volume 1102 of used fluid bufferis less than or equal to the fifth volume 1002 moved from the commonfluid buffer reservoir 111, in other examples, the sixth volume 1102 ofused fluid buffer is greater than the fifth volume 1002 moved from thecommon fluid buffer reservoir 111, and, in other examples, the sixthvolume 1102 of used fluid buffer is equal to the total amount of fluidbuffer flushed through the fluidic device 102, i.e., the combined fourthvolume 902 moved from the second fluid buffer reservoir 115 and fifthvolume 1002 moved from the common fluid buffer reservoir 111.

Referring to FIG. 12, the system 100 may be set to perform a thirdreagent operation, such that flow control valve 104 permits fluid flowfrom the selected third reagent fluid reservoir 116 of the set ofreservoirs 110 to the fluidic device 102. During the third reagentoperation, the flow control valve 104 is set to connect the thirdreagent fluid reservoir 116 to the fluidic device 102 (e.g., byconnecting valve selector channel 152 with the corresponding connectingchannel 131 associated with the third reagent fluid reservoir 116). Thepump 106 is operated to draw the third reagent fluid 126 from the thirdreagent fluid reservoir 116 through the flow control valve 104 and intothe fluidic device 102. As shown in FIG. 12, an aliquot 1202 of thethird reagent fluid 126 is moved through the corresponding connectingchannel 131, the flow control valve 104, the inlet channel 103, thefluidic device 102, the outlet channel 105, and/or into a chamber of thepump 106.

Referring to FIG. 13, the system 100 may be set to perform a thirdreagent reverse operation, such that the pump 106 redirects at least aportion of the aliquot 1202 of the third reagent fluid 126 moved in thethird reagent operation back into the third reagent fluid reservoir 116.During the third reagent reverse operation, the flow control valve 104remains set to connect the fluidic device 102 to the third reagent fluidreservoir 116, and the pump 106 is operated to expel fluid in a reversedirection through the fluidic device 102 to the third reagent fluidreservoir 116. As shown in FIG. 13, at least a portion 1302 of thealiquot 1202 of the third reagent fluid 126 moved in the third reagentoperation is received back in the third reagent fluid reservoir 116 tobe reused for one or more subsequent third reagent operations.

Referring to FIGS. 14 and 15, the system 100 may be set to perform athird wash operation, such that flow control valve 104 initially permitsfluid flow from the selected third fluid buffer reservoir 117 of the setof reservoirs 110 to the fluidic device 102, and then, optionally,permits fluid flow from the common fluid buffer reservoir 111 of the setof reservoirs 110 to the fluidic device 102.

As shown in FIG. 14, during a first part of the third wash operation,the flow control valve 104 is set to connect the third fluid bufferreservoir 117 to the fluidic device 102 (e.g., by connecting valveselector channel 152 with the corresponding connecting channel 131associated with the third buffer reservoir 117). Pump 106 is operated todraw an aliquot of the third fluid buffer 127 from the third fluidbuffer reservoir 117 through the fluidic device 102. As shown in FIG.14, a seventh volume 1402 of the third fluid buffer 127 is moved throughthe corresponding connecting channel 131, the flow control valve 104,the inlet channel 103, the fluidic device 102, the outlet channel 105,and/or into a chamber of the pump 106 to flush the third reagent fluid126 remaining in the fluidic device 102. In some implementations, theseventh volume 1402 may include a volume 1602 of reused third fluidbuffer, shown in FIG. 16, in instances where the third fluid buffer 127has previously been pumped into the corresponding connecting channel131, the flow control valve 104, the inlet channel 103, the fluidicdevice 102, the outlet channel 105, and/or a chamber of the pump 106.

As shown in FIG. 15, in some examples, during a second part of the thirdwash operation, after the seventh volume 1402 of the third fluid buffer126 is flushed through the fluidic device 102, the flow control valve104 is set to connect the common fluid buffer reservoir 111 to thefluidic device 102 (e.g., by connecting valve selector channel 152 withthe corresponding connecting channel 131 associated with the commonfluid buffer reservoir 111). Pump 106 is operated to draw an aliquot ofthe common fluid buffer 121 from the common fluid buffer reservoir 111through the fluidic device 102. As shown in FIG. 15, an eighth volume1502 of the common fluid buffer 121 can be moved through thecorresponding connecting channel 131, the flow control valve 104, theinlet channel 103, the fluidic device 102, the outlet channel 105,and/or into a chamber of the pump 106. In some implementations, theeighth volume 1502 can mix with the seventh volume 1402 in one or moreof the corresponding connecting channel 131, the flow control valve 104,the inlet channel 103, the fluidic device 102, the outlet channel 105,and/or a chamber of the pump 106. Thus, if the seventh volume 1402includes a volume 1602 of reused third fluid buffer, shown and describedin FIG. 16, the inclusion of the common fluid buffer 121 can dilute orotherwise lessen the presence of remnant third reagent fluid 126 in thereused third fluid buffer. In addition, by providing the common fluidbuffer 121 after the reused third fluid buffer, the common fluid buffer121 can fluidically separate the reused third fluid buffer furtherdownstream from the fluidic device 102.

In other examples, the second part of the second wash operationillustrated in FIG. 15 may be omitted and only the third fluid buffer127 for third wash operation can be drawn from the third fluid bufferreservoir 117.

Referring to FIG. 16, the system 100 may be set to perform a thirdbuffer reverse operation such that flow control valve 104 permits fluidflow to the third fluid buffer reservoir 127. The pump 106 redirects aninth volume 1602 of used fluid buffer comprising the third fluid buffer127 and/or the common fluid buffer 121 back to the third fluid bufferreservoir 117. The ninth volume 1602 can include at least a portion ofremnant third reagent fluid 126 in addition to the third fluid buffer127 and/or the common fluid buffer 121. In some instances, thepercentage of the common fluid buffer 121 in the ninth volume 1602 isgreater than a percentage of third fluid buffer 127 and/or reused thirdfluid buffer. During the third buffer reverse operation, the flowcontrol valve 104 is set to connect the fluidic device 102 to the thirdfluid buffer reservoir 117 (e.g., by connecting valve selector channel152 with the connecting channel 131 associated with the third fluidbuffer reservoir 117), and the pump 106 is operated to move fluid in areverse direction through the fluidic device 102 to the third fluidbuffer reservoir 117. As shown in FIG. 16, the ninth volume 1602 of usedfluid buffer is received back in the third fluid buffer reservoir 117 tobe reused for one or more subsequent third wash operations. In someexamples, the ninth volume 1602 of used fluid buffer is less than orequal to the eighth volume 1502 moved from the common fluid bufferreservoir 111, in other examples, the ninth volume 1602 of used fluidbuffer is greater than the eighth volume 1502 moved from the commonfluid buffer reservoir 111, and, in other examples, the ninth volume1602 of used fluid buffer is equal to the total amount of fluid bufferflushed through the fluidic device 102, i.e., the combined seventhvolume 1402 moved from the third fluid buffer reservoir 117 and eighthvolume 1502 moved from the common fluid buffer reservoir 111.

Referring to FIG. 17, the system 100 may be set to perform a fourthreagent operation, such that flow control valve 104 permits fluid flowfrom the selected fourth reagent fluid reservoir 118 of the set ofreservoirs 110 to the fluidic device 102. During the fourth reagentoperation, the flow control valve 104 is set to connect the fourthreagent fluid reservoir 118 to the fluidic device 102 (e.g., byconnecting valve selector channel 152 with the corresponding connectingchannel 131 associated with the fourth reagent fluid reservoir 118). Thepump 106 is operated to draw the fourth reagent fluid 128 from thefourth reagent fluid reservoir 118 through the flow control valve 104and into the fluidic device 102. As shown in FIG. 17, an aliquot 1702 ofthe fourth reagent fluid 128 is moved through the correspondingconnecting channel 131, the flow control valve 104, the inlet channel103, the fluidic device 102, the outlet channel 105, and/or into achamber of the pump 106.

Referring to FIG. 18, the system 100 may be set to perform a fourthreagent reverse operation, such that the pump 106 redirects at least aportion of the aliquot 1702 of the fourth reagent fluid 128 moved in thefourth reagent operation back into the fourth reagent fluid reservoir118. During the fourth reagent reverse operation, the flow control valve104 remains set to connect the fluidic device 102 to the fourth reagentfluid reservoir 118, and the pump 106 is operated to expel fluid in areverse direction through the fluidic device 102 to the fourth reagentfluid reservoir 118. As shown in FIG. 18, at least a portion 1802 of thealiquot 1702 of the fourth reagent fluid 128 moved in the fourth reagentoperation is received back in the fourth reagent fluid reservoir 118 tobe reused for subsequent fourth reagent operation.

In some examples, it may not be feasible or practical to reuse a fluidbuffer after a wash operation—for example, if the characteristics ofreagent or other material being flushed in the wash operation are suchthat the risk of carryover from re-using a buffer used to flush thereagent are too great. In one example, combining fluid buffer used toflush reagents in the fluidic device 102 after a scavenger process ofthe SBS operation with fresh buffer typically compromises the subsequentprocesses of the SBS operation, even if a trace amount of the used fluidbuffer was added to the fresh buffer. In such a situation, buffer may bemoved through the fluidic device, for example, from the common bufferreservoir 111, but the used buffer is not thereafter reversed back to asequestered fluid buffer reservoir. In some examples, the risk ofreusing a fluid buffer is determined to be too great when the used fluidbuffer exceeds a first contamination level, which may be determined byexperimentation.

In some examples, the system 100 may reuse fluid buffer from the samedesignated reservoir in two different wash operations that follow twodifferent reagent operations. For example, if the characteristics of thereagent or other material of a first reagent operation are benign,meaning that the presence of the reagent or the material would notaffect or compromise another reagent operation (e.g., a second reagentoperation), then the fluid buffer used to flush that reagent or materialafter the first reagent operation may be used again in the washoperation following the second reagent operation. In some examples, aused fluid buffer is determined be benign when the used fluid buffer isbelow a second contamination level, which may be determined byexperimentation.

Referring to FIG. 19, the system 100 may be set to perform a fourth washoperation, such that flow control valve 104 permits fluid flow from theselected common fluid buffer reservoir 111 of the set of reservoirs 110to the fluidic device 102. As shown in FIG. 19, a volume 1902 of thecommon fluid buffer 121 is moved through the corresponding connectingchannel 131, the flow control valve 104, the inlet channel 103, thefluidic device 102, the outlet channel 105, and/or into a chamber of thepump 106 to flush the fourth reagent fluid 128 remaining in the fluidicdevice 102. The system 100, however, does not include a fluid bufferreservoir for storing and sequestering the buffer used in the fourthwash operation for possible re-use. Thus, the volume 1902 of buffermoved through the fluidic device during the fourth wash operation is notreversed from the corresponding connecting channel 131, the flow controlvalve 104, the inlet channel 103, the fluidic device 102, the outletchannel 105, and/or a chamber of the pump 106. Rather, the fluid buffermay be flushed through the corresponding connecting channel 131, theflow control valve 104, the inlet channel 103, the fluidic device 102,the outlet channel 105, and/or a chamber of the pump 106 and moved intoa waste reservoir (not shown).

Method for Sequestering and Reusing Reagent Fluid and Fluid Buffer

According to various examples, FIG. 20 illustrates a method 2000 forsequestering and reusing reagent fluids and fluid buffers.

Method 2000 comprises a step 2010 of moving an aliquot of first reagentfluid 122 into the fluidic device 102. In some examples, step 2010comprises setting the flow control valve 104 to permit fluid flow fromthe first reagent fluid reservoir 112 to the fluidic device 102. In someexamples, step 2010 comprises actuating a motor to rotate the flowcontrol valve 104 to align and fluidly connect the valve selectorchannel 152 with a corresponding connecting channel 131 associated withthe first reagent fluid reservoir 112. In some examples, step 2010comprises using the pump 106 to move the first reagent fluid 122 fromthe first reagent fluid reservoir 112 to the fluidic device 102. In someexamples, step 2010 comprises using the actuator to move the plunger ofthe syringe pump 106 in the first direction to generate a negativepressure differential to move the first reagent fluid 122 through thefluidic device 102.

Method 2000 may further comprise a step 2015 of moving a volume of fluidbuffer into the fluidic device 102. In some examples, step 2015 includesa first part comprising moving a volume of the first fluid buffer 123from the first fluid buffer reservoir 113 into the fluidic device 102.In some examples, the first part of step 2015 comprises setting the flowcontrol valve 104 to permit fluid flow from the first fluid bufferreservoir 113 to the fluidic device 102 and using the pump 106 to movethe first fluid buffer 123 from the first fluid buffer reservoir 113 tothe fluidic device 102. In some examples, the first part of step 2015comprises actuating the motor to rotate the flow control valve 104 toalign and fluidly connect the valve selector channel 152 with acorresponding connecting channel 131 associated with the first fluidbuffer reservoir 113. In some examples, the first part of step 2015comprises using the actuator to move the plunger of the syringe pump 106in the first direction to generate a negative pressure differential tomove the first fluid buffer 123 through the fluidic device 102.

In some examples, step 2015 includes a second part comprising, aftermoving the first fluid buffer 123, moving a volume of the common fluidbuffer 121 from the common fluid buffer reservoir 111 into the fluidicdevice 102. In some examples, the second part of step 2015 comprisessetting the flow control valve 104 to permit fluid flow from the commonfluid buffer reservoir 111 to the fluidic device 102 and using the pump106 to move the common fluid buffer 121 from the common fluid bufferreservoir 111 to the fluidic device 102. In some examples, the secondpart of step 2015 comprises actuating the motor to rotate the flowcontrol valve 104 to align and fluidly connect the valve selectorchannel 152 with a corresponding connecting channel 131 associated withthe common fluid buffer reservoir 111. In some examples, the second partof step 2015 comprises using the actuator to move the plunger of thesyringe pump 106 in the first direction to generate a negative pressuredifferential to move the common fluid buffer 121 through the fluidicdevice 102.

In some examples, the volume of first fluid buffer 123 moved from thefirst fluid buffer reservoir 113 is substantially equal to the volume ofthe common fluid buffer 121 moved from the common fluid buffer reservoir111. In other instances, the volume of first fluid buffer 123 moved fromthe first fluid buffer reservoir 113 is greater than the volume of thecommon fluid buffer 121 moved from the common fluid buffer reservoir111. In still other instances, the volume of first fluid buffer 123moved from the first fluid buffer reservoir 113 is less than the volumeof the common fluid buffer 121 moved from the common fluid bufferreservoir 111.

Method 2000 may further comprise a step 2020 of moving at least aportion of the volume of the fluid buffer moved in step 2015 into thefirst fluid buffer reservoir 113. In some examples, step 2020 comprisessetting the flow control valve 104 to permit flow from the fluidicdevice 102 to the first fluid buffer reservoir 113. In some examples,step 2020 comprises actuating the motor to rotate the flow control valve104 to align and fluidly connect the valve selector channel 152 with acorresponding connecting channel 131 associated with the first fluidbuffer reservoir 113. In some examples, step 2020 comprises using thepump 106 to expel the fluid buffer from the fluidic device 102 to thefirst fluid buffer reservoir 113. In some examples, step 2020 comprisesusing the actuator to move the plunger of the syringe pump 106 in thesecond direction to generate a positive pressure differential to movethe fluid buffer to the first fluid buffer reservoir 113. In someexamples, the portion of fluid buffer moved to the first fluid bufferreservoir 113 in step 2020 ranges from about 30% to 70% of the totalvolume of fluid buffer moved into the fluidic device 102 in step 2015.For example, if 50 μL of first fluid buffer 123 is moved from the firstfluid buffer reservoir 113 and 50 μL of common fluid buffer 121 movedfrom the common fluid buffer reservoir 111, then a volume of 30 μL to 70μL of the combined 100 μL volume can be moved back into the first fluidbuffer reservoir 113. In some instances, the volume moved back into thefirst fluid buffer reservoir 113 can be predominantly common fluidbuffer 121 based on the common fluid buffer displacing the first fluidbuffer 123 further downstream through the fluidic system.

Method 2000 may further comprise a step 2025 of moving an aliquot ofsecond reagent fluid 124 into the fluidic device 102. In some examples,step 2025 comprises setting the flow control valve 104 to permit fluidflow from the second reagent fluid reservoir 114 to the fluidic device102. In some examples, step 2025 comprises actuating the motor to rotatethe flow control valve 104 to align and fluidly connect the valveselector channel 152 with a corresponding connecting channel 131associated with the second reagent fluid reservoir 114. In someexamples, step 2025 comprises using the pump 106 to move the secondreagent fluid 124 from the second reagent fluid reservoir 114 to thefluidic device 102. In some examples, step 2025 comprises using theactuator to move the plunger of the syringe pump 106 in the firstdirection to generate a negative pressure differential to move thesecond reagent fluid 124 through the fluidic device 102

Method 2000 may further comprise a second step 2030 of moving a volumeof fluid buffer into the fluidic device 102. In some examples, step 2030includes a first part comprising moving a volume of the second fluidbuffer 125 from the second fluid buffer reservoir 115 into the fluidicdevice 102. In some examples, the first part of step 2030 comprisessetting the flow control valve 104 to permit fluid flow from the secondfluid buffer reservoir 115 to the fluidic device 102 and using the pump106 to move the second fluid buffer 125 from the second fluid bufferreservoir 115 to the fluidic device 102. In some examples, the firstpart of step 2030 comprises actuating the motor to rotate the flowcontrol valve 104 to align and fluidly connect the valve selectorchannel 152 with a corresponding connecting channel 131 associated withthe second fluid buffer reservoir 115. In some examples, the first partof step 2030 comprises using the actuator to move the plunger of thesyringe pump 106 in the first direction to generate a negative pressuredifferential to move the second fluid buffer 125 through the fluidicdevice 102.

In some examples, step 2030 includes a second part comprising, aftermoving the second fluid buffer 125, moving a volume of the common fluidbuffer 121 from the common fluid buffer reservoir 111 into the fluidicdevice 102. In some examples, the second part of step 2030 comprisessetting the flow control valve 104 to permit fluid flow from the commonfluid buffer reservoir 111 to the fluidic device 102 and using the pump106 to draw the volume of the common fluid buffer 121 from the commonfluid buffer reservoir 111 to the fluidic device 102. In some examples,the second part of step 2030 comprises actuating the motor to rotate theflow control valve 104 to align and fluidly connect the valve selectorchannel 152 with a corresponding connecting channel 131 associated withthe common fluid buffer reservoir 111. In some examples, the second partof step 2030 comprises using the actuator to move the plunger of thesyringe pump 106 in the first direction to generate a negative pressuredifferential to move the common fluid buffer 121 through the fluidicdevice 102.

Method 2000 may further comprise a step 2035 of moving at least aportion of the volume of the fluid buffer moved in step 2030 into thesecond fluid buffer reservoir 115. In some examples, step 2035 comprisessetting the flow control valve 104 to permit flow from the fluidicdevice 102 to the second fluid buffer reservoir 115. In some examples,step 2035 comprises actuating the motor to rotate the flow control valve104 to align and fluidly connect the valve selector channel 152 with acorresponding connecting channel 131 associated with the second fluidbuffer reservoir 115. In some examples, step 2035 comprises using thepump 106 to expel the fluid buffer from the fluidic device 102 to thesecond fluid buffer reservoir 115. In some examples, step 2035 comprisesusing the actuator to move the plunger of the syringe pump 106 in thesecond direction to generate a positive pressure differential to movethe fluid buffer to the second fluid buffer reservoir 115. In someexamples, the portion of fluid buffer moved to the second fluid bufferreservoir 115 in step 2035 ranges from about 30% to 70% of the totalvolume of fluid buffer moved into the fluidic device 102 in step 2030.For example, if 50 μL of second fluid buffer 125 is moved from thesecond fluid buffer reservoir 115 and 50 μL of common fluid buffer 121moved from the common fluid buffer reservoir 111, then a volume of 30 μLto 70 μL of the combined 100 μL volume can be moved back into the secondfluid buffer reservoir 115. In some instances, the volume moved backinto the second fluid buffer reservoir 115 can be predominantly commonfluid buffer 121 based on the common fluid buffer displacing the secondfluid buffer 125 further downstream through the fluidic system.

Method 2000 may further comprise a step 2040 of re-using the firstreagent fluid 122 by moving an aliquot of the first reagent fluid 122into the fluidic device 102. In some examples, step 2040 comprisessetting the flow control valve 104 to permit fluid flow from the firstreagent fluid reservoir 112 to the fluidic device 102. In some examples,step 2040 comprises actuating the motor to rotate the flow control valve104 to align and fluidly connect the valve selector channel 152 with acorresponding connecting channel 131 associated with the first reagentfluid reservoir 112. In some examples, step 2040 comprises using thepump 106 to move the first reagent fluid 122 from the first reagentfluid reservoir 112 to the fluidic device 102. In some examples, step2040 comprises using the actuator to move the plunger of the syringepump 106 in the first direction to generate a negative pressuredifferential to move the first reagent fluid 122 through the fluidicdevice 102

Method 2000 may further comprise a step 2045 of re-using the first fluidbuffer by moving a volume of fluid buffer into the fluidic device 102,where at least a portion of the volume of fluid buffer moved in step2045 is moved from the first fluid buffer reservoir 113, which nowincludes used fluid buffer moved to first fluid buffer reservoir 113 instep 2020. In some examples, step 2045 includes a first part comprisingsetting the flow control valve 104 to permit fluid flow from the firstfluid buffer reservoir 113 to the fluidic device 102. In some examples,the first part of step 2045 comprises setting the flow control valve 104to permit fluid flow from the first fluid buffer reservoir 113 to thefluidic device 102 and using the pump 106 to move the first fluid buffer123 from the first fluid buffer reservoir 113 to the fluidic device 102.In some examples, the first part of step 2045 comprises actuating themotor to rotate the flow control valve 104 to align and fluidly connectthe valve selector channel 152 with a corresponding connecting channel131 associated with the first fluid buffer reservoir 113. In someexamples, the first part of step 2045 comprises using the actuator tomove the plunger of the syringe pump 106 in the first direction togenerate a negative pressure differential to move the first fluid buffer123 through the fluidic device 102.

In some examples, step 2045 includes a second part comprising, aftermoving the first fluid buffer 123, moving a volume of the common fluidbuffer 121 from the common fluid buffer reservoir 111 into the fluidicdevice 102. In some examples, the second part of step 2045 comprisessetting the flow control valve 104 to permit fluid flow from the commonfluid buffer reservoir 111 to the fluidic device 102 and using the pump106 to move the common fluid buffer 121 from the common fluid bufferreservoir 111 to the fluidic device 102. In some examples, the secondpart of step 2045 comprises actuating the motor to rotate the flowcontrol valve 104 to align and fluidly connect the valve selectorchannel 152 with a corresponding connecting channel 131 associated withthe common fluid buffer reservoir 111. In some examples, the second partof step 2045 comprises using the actuator to move the plunger of thesyringe pump 106 in the first direction to generate a negative pressuredifferential to move the common fluid buffer 121 through the fluidicdevice 102. In some examples, the volume of first fluid buffer 123 movedfrom the first fluid buffer reservoir 113 is substantially equal to thevolume of the common fluid buffer 121 moved from the common fluid bufferreservoir 111.

In some examples, if the first fluid buffer 123 is to be further re-usedafter step 2045, the method comprises a step of moving at least aportion of the volume fluid buffer moved in step 2045 back into thefirst fluid buffer reservoir 113, as in step 2020 above. In someexamples, the step of moving at least a portion of the volume fluidbuffer moved in step 2045 back into the first fluid buffer reservoir 113comprises setting the flow control valve 104 to permit flow from thefluidic device 102 to the first fluid buffer reservoir 113. In someexamples, the step of moving at least a portion of the volume fluidbuffer moved in step 2045 back into the first fluid buffer reservoir 113comprises actuating the motor to rotate the flow control valve 104 toalign and fluidly connect the valve selector channel 152 with acorresponding connecting channel 131 associated with the first fluidbuffer reservoir 113. In some examples, the step of moving at least aportion of the volume fluid buffer moved in step 2045 back into thefirst fluid buffer reservoir 113 comprises using the actuator to movethe plunger of the syringe pump 106 in the second direction to generatea positive pressure differential to move the fluid buffer to the firstfluid buffer reservoir 113. In some examples, the portion of fluidbuffer moved from the first fluid buffer reservoir 113 in step 2045ranges from about 30% to 70% of the volume of the fluid buffer movedinto the fluidic device 102 in step 2045.

Method 2000 may further comprise a step 2050 of re-using the secondreagent fluid 124 by moving an aliquot of the second reagent fluid 124into the fluidic device 102. In some examples, step 2050 comprisessetting the flow control valve 104 to permit fluid flow from the secondreagent fluid reservoir 114 to the fluidic device 102. In some examples,step 2050 comprises actuating the motor to rotate the flow control valve104 to align and fluidly connect the valve selector channel 152 with acorresponding connecting channel 131 associated with the second reagentfluid reservoir 114. In some examples, step 2050 comprises using thepump 106 to draw move the second reagent fluid 124 from the secondreagent fluid reservoir 114 to the fluidic device 102. In some examples,step 2050 comprises using the actuator to move the plunger of thesyringe pump 106 in the first direction to generate a negative pressuredifferential to move the second reagent fluid 124 through the fluidicdevice 102.

Method 2000 may further comprise a step 2055 of re-using the secondfluid buffer by moving a volume of fluid buffer into the fluidic device102, where at least a portion of the volume of fluid buffer moved instep 2055 is moved from the second fluid buffer reservoir 115, which nowincludes used fluid buffer moved to second fluid buffer reservoir 115 instep 2035. In some examples, step 2055 includes a first part comprisingsetting the flow control valve 104 to permit fluid flow from the secondfluid buffer reservoir 115 to the fluidic device 102. In some examples,the first part of step 2055 comprises setting the flow control valve 104to permit fluid flow from the second fluid buffer reservoir 115 to thefluidic device 102 and using the pump 106 to move the second fluidbuffer 125 from the second fluid buffer reservoir 115 to the fluidicdevice 102. In some examples, the first part of step 2055 comprisesactuating the motor to rotate the flow control valve 104 to align andfluidly connect the valve selector channel 152 with a correspondingconnecting channel 131 associated with the second fluid buffer reservoir115. In some examples, the first part of step 2055 comprises using theactuator to move the plunger of the syringe pump 106 in the firstdirection to generate a negative pressure differential to move thesecond fluid buffer 125 through the fluidic device 102.

In some examples, step 2055 includes a second part comprising, aftermoving the second fluid buffer 125, moving a volume of the common fluidbuffer 121 from the common fluid buffer reservoir 111 into the fluidicdevice 102. In some examples, the second part of step 2055 comprisessetting the flow control valve 104 to permit fluid flow from the commonfluid buffer reservoir 111 to the fluidic device 102 and using the pump106 to move the common fluid buffer 121 from the common fluid bufferreservoir 111 to the fluidic device 102. In some examples, the secondpart of step 2055 comprises actuating the motor to rotate the flowcontrol valve 104 to align and fluidly connect the valve selectorchannel 152 with a corresponding connecting channel 131 associated withthe common fluid buffer reservoir 111. In some examples, the second partof step 2055 comprises using the actuator to move the plunger of thesyringe pump 106 in the first direction to generate a negative pressuredifferential to move the common fluid buffer 121 through the fluidicdevice 102. In some examples, the volume of second fluid buffer 125moved from the second fluid buffer reservoir 115 is substantially equalto the volume of the common fluid buffer 121 moved from the common fluidbuffer reservoir 111.

In some examples, if the second fluid buffer 125 is to be furtherre-used after step 2055, the method comprises a step of moving at leasta portion of the volume fluid buffer moved in step 2055 back into thesecond fluid buffer reservoir 115, as in step 2035. In some examples,the step of moving at least a portion of the volume fluid buffer movedin step 2055 back into the second fluid buffer reservoir 115 comprisessetting the flow control valve 104 to permit flow from the fluidicdevice 102 to the second fluid buffer reservoir 115. In some examples,the step of moving at least a portion of the volume fluid buffer movedin step 2055 back into the second fluid buffer reservoir 115 comprisesactuating the motor to rotate the flow control valve 104 to align andfluidly connect the valve selector channel 152 with a correspondingconnecting channel 131 associated with the second fluid buffer reservoir115. In some examples, the step of moving at least a portion of thevolume fluid buffer moved in step 2055 back into the second fluid bufferreservoir 115 comprises using the actuator to move the plunger of thesyringe pump 106 in the second direction to generate a positive pressuredifferential to move the fluid buffer to the second fluid bufferreservoir 115.

Processing Instrument

As schematically shown in FIG. 21, in some examples, the system 100includes a fluid cartridge 52 supporting various components of thesystem 100, such as, the fluidic device 102, the flow control valve 104,the pump 106, and the set of fluid reservoirs 110 The fluid cartridge 52may be operatively installed into a processing instrument 50. In someexamples, the fluid cartridge 52 includes the inlet channel 103, theflow control valve 104, at least part of the outlet channel 105, the setof fluid reservoirs 110, and the set of connecting channels 130. Thefluidic device 52 may be operatively coupled to the instrument 50, andthe instrument 50 may include one or more actuators (e.g., motor) tocontrol the position flow control valve 104 and the pressure applied bythe pump 106 to select and move various reagent fluids and fluidbuffers. Instrument 50 may further include a waste outlet (not shown) todispose any used reagent fluid or fluid buffer. Controller 140, whichmay be part of the instrument 50 or may be a standalone or remotecomputer resource operatively connected to the instrument 50, controlsoperation of the instrument 50 (e.g., processing of the fluidic device102 and operation of the pump 106) and operation of the fluid cartridge52 (e.g., operation of the flow control valve 104).

Hardware and Software

Aspects of the disclosure are implemented via control and computinghardware components, user-created software, data input components, anddata output components. Hardware components include computing andcontrol modules (e.g., system controller(s)), such as microprocessorsand computers, configured to effect computational and/or control stepsby receiving one or more input values, executing one or more algorithms,as the algorithm described in FIG. 20, stored on non-transitorymachine-readable media (e.g., software) that provide instruction formanipulating or otherwise acting on the input values, and output one ormore output values. Such outputs may be displayed or otherwise indicatedto a user for providing information to the user, for example informationas to the status of the instrument or a process being performed thereby,or such outputs may comprise inputs to other processes and/or controlalgorithms. Data input components comprise elements by which data isinput for use by the control and computing hardware components. Suchdata inputs may comprise positions sensors, motor encoders, as well asmanual input elements, such as graphic user interfaces, keyboards, touchscreens, microphones, switches, manually-operated scanners,voice-activated input, etc. Data output components may comprise harddrives or other storage media, graphic user interfaces, monitors,printers, indicator lights, or audible signal elements (e.g., buzzer,horn, bell, etc.). Software comprises instructions stored onnon-transitory computer-readable media which, when executed by thecontrol and computing hardware, cause the control and computing hardwareto perform one or more automated or semi-automated processes.

In some examples, the apparatus may include a control system including acomputer controller 140 (schematically represented in FIGS. 1-19).Controller 140 may be a control system or computer connected to any oneof the devices of the system 100, e.g., a stand-alone computer, or mayinclude computer components integrated with any one of the devices ofthe system 100, e.g., an application specific integrated circuit. Thesecomputer components can include one or more microprocessors, displays,keyboards (and/or other user input devices), memory components,printer(s), and/or other devices. Controller 140 may be configured toreceive inputs from a user (e.g., user-inputs) and/or feedback devices,such as pressure sensors, flow meters, etc., and manage the performanceof the fluid operations of the system 100. Controller 140 may includesoftware algorithms to implement processes, such as a processimplementing the method 2000 shown in FIG. 20, that enable a user toenter user-defined parameters related to fluid processing operationsinto the fluidic device 102 of the system 100, schedule different fluidprocessing operations on the fluidic device 102 of the system 100,and/or cause the controller 140 to perform the different stepsassociated with the fluid processing operations, monitor the performanceof the fluid processing operations, and/or output results (on display,printout, etc.) for the user.

As shown in FIGS. 1-19, the controller 140 is in electricalcommunication with the flow control valve 104, the pump 106 (indicatedby the dashed lines), and/or intermediary devices configured to controlthe flow control valve 104 and/or the pump 106 (e.g., a step motor forthe flow control valve 104, a motor for the pump 106, etc.) such thatthe controller 140 may send instructions to control the control valve104 and the pump 106 to perform different steps associated with thefluid processing operations (e.g., the processes associated with FIGS.2-19 and/or the method of FIG. 20). In some examples, the controller 140is configured to transmit a command for the flow control valve 104 tofluidly connect a selected fluid reservoir of the set of reservoirs 110to the inlet channel 103 so that the fluid from the selected fluidreservoir may flow through the corresponding connecting channel 131, theflow control valve 104, the inlet channel 103, the fluidic device 102,the outlet channel 105, and/or a chamber of the pump 106. In someexamples, the controller 140 is configured to transmit a command to thepump 106 to move in the first or second direction to generate a pressuredifferential between the any one of the set of the fluid reservoirs 110and the outlet channel 105 to drive fluid flow towards or away from thepump 106.

In some examples, the controller 140 is configured to access a computerreadable medium encoded with computer-executable instructions to performthe different processes described herein. In some examples, by executingthe instructions encoded in the computer readable medium, the controller140 causes the system 100 to execute the methods and processes, orportions thereof, described herein, including: (a) move an aliquot offirst reagent fluid into the fluidic device; (b) after process (a), movea volume of fluid buffer into the fluidic device; (c) after process (b),move at least a portion of the volume of fluid buffer moved in process(b) into a first fluid buffer reservoir; (d) after process (c), move analiquot of second reagent fluid into the fluidic device; (e) afterprocess (d), move a volume of fluid buffer into the fluidic device;and/or, (f) after process (e), move at least a portion of the volume offluid buffer moved in process (e) into a second fluid buffer reservoir.

It should be appreciated that all combinations of the foregoing conceptsand additional concepts discussed in greater detail below (provided suchconcepts are not mutually inconsistent) are contemplated as being partof the inventive subject matter disclosed herein. In particular, allcombinations of claimed subject matter appearing at the end of thisdisclosure are contemplated as being part of the inventive subjectmatter disclosed herein. It should also be appreciated that terminologyexplicitly employed herein that also may appear in any disclosureincorporated by reference should be accorded a meaning most consistentwith the particular concepts disclosed herein.

While the subject matter of this disclosure has been described and shownin considerable detail with reference to certain illustrative examples,including various combinations and sub-combinations of features, thoseskilled in the art will readily appreciate other examples and variationsand modifications thereof as encompassed within the scope of the presentdisclosure. Moreover, the descriptions of such examples, combinations,and sub-combinations is not intended to convey that the claimed subjectmatter requires features or combinations of features other than thoseexpressly recited in the claims. Accordingly, the scope of thisdisclosure is intended to include all modifications and variationsencompassed within the spirit and scope of the following appendedclaims.

1. A method comprising: (a) moving an aliquot of first reagent fluidinto a fluidic device; (b) after step (a), moving a volume of fluidbuffer into the fluidic device; (c) after step (b), moving at least aportion of the volume of fluid buffer moved in step (b) into a firstfluid buffer reservoir; (d) after step (c), moving an aliquot of secondreagent fluid into the fluidic device; (e) after step (d), moving avolume of fluid buffer into the fluidic device; and (f) after step (e),moving at least a portion of the volume of fluid buffer moved in step(e) into a second fluid buffer reservoir.
 2. The method of claim 1further comprising: (g) after step (f), moving an aliquot of the firstreagent fluid into the fluidic device; (h) after step (g), moving avolume of fluid buffer into the fluidic device, wherein at least aportion of the volume of fluid buffer moved in step (h) is moved fromthe first fluid buffer reservoir; (i) after step (h), moving an aliquotof the second reagent fluid into the fluidic device; and (j) after step(i), moving a volume of fluid buffer into the fluidic device, wherein atleast a portion of the volume of fluid buffer moved in step (j) is movedfrom the second fluid buffer reservoir.
 3. The method of claim 2,further comprising: (k) after step (h) and before step (i), moving atleast a portion of the volume moved in step (h) back into the firstfluid buffer reservoir; and (l) after step (j), moving at least aportion of the volume moved in step (j) back into the second fluidbuffer reservoir.
 4. The method of claim 1, wherein step (b) comprisesmoving a volume of fluid buffer from the first fluid buffer reservoirinto the fluidic device, and thereafter, moving a volume of fluid bufferfrom a common fluid buffer reservoir into the fluidic device, andwherein step (e) comprises moving a volume of fluid buffer from thesecond fluid buffer reservoir into the fluidic device, and thereafter,moving a volume of fluid buffer from the common fluid buffer reservoirinto the fluidic device.
 5. The method of claim 4, wherein step (b), thevolume of fluid buffer moved from the first fluid buffer reservoir issubstantially equal to the volume of fluid buffer moved from the commonfluid buffer reservoir.
 6. The method of claim 1, wherein step (b)comprises moving a volume of fluid buffer from the first fluid bufferreservoir into the fluidic device; and wherein step (e) comprises movinga volume of fluid buffer from the second fluid buffer reservoir into thefluidic device.
 7. The method of claim 1, wherein the portion of fluidbuffer moved to the first fluid buffer reservoir in step (c) ranges fromabout 30% to 70% of the volume of fluid buffer moved in step (b).
 8. Themethod of claim 2, wherein in step (h), the portion of fluid buffermoved from the first fluid buffer reservoir ranges from about 30% to 70%of the volume of fluid buffer moved into the fluidic device.
 9. Themethod of claim 1, wherein in step (d), the aliquot of the secondreagent is not mixed with the aliquot of the first reagent in thefluidic device.
 10. A system comprising: a fluidic device; a flowcontrol valve; a first reagent fluid reservoir fluidly connectable tothe fluidic device by the flow control valve; a first fluid bufferreservoir fluidly connectable to the fluidic device by the flow controlvalve; a common fluid buffer source fluidly connectable to the fluidicdevice by the flow control valve; and wherein the flow control valvepermits flow comprising: (i) flow from the first reagent fluid reservoirto the fluidic device, (ii) flow from the common fluid buffer source tothe fluidic device, (iii) flow from the fluidic device to the firstfluid buffer reservoir, (iv) flow from the first reagent fluid reservoirto the fluidic device, and (v) flow from the first fluid bufferreservoir to the fluidic device.
 11. The system of claim 10 furthercomprising: a second reagent fluid reservoir fluidly connectable to thefluidic device by the flow control valve; and a second fluid bufferreservoir fluidly connectable to the fluidic device by the flow controlvalve; wherein the flow control valve permits flow further comprising:(vi) flow from the second reagent fluid reservoir to the fluidic device,(vii) flow from the second fluid buffer reservoir to the fluidic device,(viii) flow from the common fluid buffer source to the fluidic device,and (ix) flow from the fluidic device to the second fluid bufferreservoir.
 12. The system of claim 10, wherein the first fluid bufferreservoir comprises a cache channel comprising a consistentcross-sectional dimension across a length thereof.
 13. The system ofclaim 10, wherein the first fluid buffer reservoir is fluidly connectedto the fluidic device by a channel, and the fluid buffer reservoircomprises a cache reservoir comprising a cross-sectional dimensionlarger than a cross-sectional dimension of the channel.
 14. The systemof claim 10 further comprising a syringe pump operatively associatedwith the fluidic device, the first reagent fluid reservoir, the commonfluid buffer source, and the first fluid buffer reservoir such that thesyringe pump generates a pressure differential between the fluidicdevice and any one of the first reagent fluid reservoir, the commonfluid buffer source, or the first fluid buffer reservoir to drive fluidflow.
 15. The system of claim 10, wherein the flow control valve is arotary valve.
 16. The system of claim 10 further comprising a controllerin electrical communication with the flow control valve for transmittingcommands controlling operation of the flow control valve to perform thesequence.
 17. The system of claim 10, wherein the first fluid bufferreservoir holds a first volume of fluid that is at least 30% of a volumeof fluid held by the fluidic device.
 18. A computer readable mediumencoded with computer-executable instructions that, when executed by acomputer controller of an automated system, causes the system to executethe following system processes: (a) move an aliquot of first reagentfluid into a fluidic device; (b) after process (a), move a volume offluid buffer into the fluidic device; (c) after process (b), move atleast a portion of the volume of fluid buffer moved in process (b) intoa first fluid buffer reservoir; (d) after process (c), move an aliquotof second reagent fluid into the fluidic device; (e) after process (d),move a volume of fluid buffer into the fluidic device; and (f) afterprocess (e), move at least a portion of the volume of fluid buffer movedin process (e) into a second fluid buffer reservoir.
 19. The computerreadable medium of claim 18, wherein the system processes furthercomprises: (g) after process (f), move an aliquot of the first reagentfluid into the fluidic device; (h) after process (g), move a volume offluid buffer into the fluidic device, wherein at least a portion of thevolume of fluid buffer moved in process (h) is moved from the firstfluid buffer reservoir; (i) after process (h), move an aliquot of thesecond reagent fluid into the fluidic device; and (j) after process (i),move a volume of fluid buffer into the fluidic device, wherein at leasta portion of the volume of fluid buffer moved in process (j) is movedfrom the second fluid buffer reservoir.
 20. The computer readable mediumof claim 18, wherein process (b) comprises move a volume of fluid bufferfrom the first fluid buffer reservoir into the fluidic device, andthereafter, moving a volume of fluid buffer from a common fluid bufferreservoir into the fluidic device, and wherein process (e) comprisesmoving a volume of fluid buffer from the second fluid buffer reservoirinto the fluidic device, and thereafter, moving a volume of fluid bufferfrom the common fluid buffer reservoir into the fluidic device.